Articulating including antagonistic controls for articulation and calibration

Abstract

A surgical tool includes a drive housing, a shaft extending from the drive housing, an end effector at an end of the shaft and having opposing jaws and a cutting element, and an articulable wrist configured to rotate the end effector within a plane. The wrist is articulated via antagonistic translation of a pair of drive members. Various systems are provided for homing one or more drive inputs that cause movement in the wrist and/or the end effector, or for controlling articulation of the drive inputs.

What is claimed is: 
     
       1. A surgical tool, comprising:
 a drive housing; 
 a shaft that extends from the drive housing; 
 a wrist arranged at an end of the shaft and including:
 a base defining an extension member extending distally from the base, and a pivot shaft defined by the base and extending from the extension member and along an articulation axis; and 
 an articulation member defining an aperture that receives the pivot shaft, the articulation member being rotatable about the articulation axis; and 
 
 a linkage assembly actuatable to articulate the wrist in a plane and including:
 a first drive member extending within the shaft from the drive housing and being operatively connected to the wrist at a first drive pin of the articulation member; and 
 a second drive member extending within the shaft from the drive housing and being operatively connected to the wrist at a second drive pin of the articulation member, 
 
 wherein actuation of the first and second drive members in opposite axial directions within the shaft causes the articulation member to rotate about the articulation axis and thereby articulate the wrist in the plane. 
 
     
     
       2. The surgical tool of  claim 1 , wherein the linkage assembly further includes a distal link that couples distal ends of the first and second drive members at the wrist. 
     
     
       3. The surgical tool of  claim 2 , wherein the first drive pin of the articulation member is disposed within a first aperture of the distal link and the second drive pin of the articulation member is disposed within a second aperture of the distal link. 
     
     
       4. The surgical tool of  claim 2 , wherein the distal link defines an interior pivot surface engageable with the base, and the distal link pivots against the interior pivot surface as the articulation member rotates about the articulation axis. 
     
     
       5. The surgical tool of  claim 1 , wherein the base is connected to a distal end of an inner grounding shaft extending within the shaft. 
     
     
       6. The surgical tool of  claim 5 , wherein the first and second drive members are arranged within first and second slots, respectively, defined on opposing sides of the inner grounding shaft. 
     
     
       7. The surgical tool of  claim 6 , wherein at least a portion of the first and second slots are defined between an upper surface of the inner grounding shaft and a lower surface of the base. 
     
     
       8. The surgical tool of  claim 5 , further comprising a first articulation yoke arranged around the inner grounding shaft and operatively coupled to a proximal end of the first drive member and a second articulation yoke arranged around the inner grounding shaft and operatively coupled to a proximal end of the second drive member, wherein axial translation of the first and second articulation yokes causes axial translation of the first and second drive members, respectively. 
     
     
       9. The surgical tool of  claim 8 , wherein the first and second articulation yokes are arranged around the inner grounding shaft such that they rotate with the inner grounding shaft. 
     
     
       10. The surgical tool of  claim 1 , further comprising:
 a first drive shaft rotatably mounted within the drive housing and operatively coupled to the first drive member such that rotation of the first drive shaft causes axial movement of the first drive member; and 
 a second drive shaft rotatably mounted within the drive housing and operatively coupled to the second drive member such that rotation of the second drive shaft causes axial movement of the second drive member. 
 
     
     
       11. The surgical tool of  claim 10 , wherein the first drive shaft is operatively coupled to the first drive member via a first gear arrangement having a gear ratio greater than or less than 1:1, and the second drive shaft is operatively coupled to the second drive member via a second gear arrangement having a gear ratio greater than or less than 1:1. 
     
     
       12. The surgical tool of  claim 10 , wherein the first drive shaft is operatively coupled to the first drive member via a first drive rack having a first yoke engageable with a first articulation yoke operatively coupled to a proximal end of the first drive member, and wherein the second drive shaft is operatively coupled to the second drive member via a second drive rack having a second yoke engageable with a second articulation yoke operatively coupled to a proximal end of the second drive member. 
     
     
       13. The surgical tool of  claim 1 , wherein the first drive member defines a first drive pin aperture that receives the first drive pin, and the second drive member defines a second drive pin aperture that receives the second drive pin, and wherein the first and second drive pin apertures are sized such that the first and second drive pins laterally translate within the first and second drive pin apertures during actuation of the first and second drive members. 
     
     
       14. The surgical tool of  claim 1 , wherein the articulation axis extends through and is perpendicular to the longitudinal axis. 
     
     
       15. The surgical tool of  claim 1 , wherein the articulation member provides an annular body that defines the aperture, and the first and second drive pins extend from the annular body on the angularly opposite sides of the aperture. 
     
     
       16. A surgical tool, comprising:
 a drive housing; 
 a shaft that extends from the drive housing along a longitudinal axis; 
 a wrist arranged at an end of the shaft and including:
 a base providing a pivot shaft that extends along an articulation axis; 
 an articulation member defining an aperture that receives the pivot shaft, the articulation member being rotatable about the articulation axis; and 
 
 a linkage assembly actuatable to articulate the wrist in a plane and including:
 a first drive member extending within the shaft from the drive housing and being operatively connected to the wrist at a first drive pin of the articulation member; and 
 a second drive member extending within the shaft from the drive housing and being operatively connected to the wrist at a second drive pin of the articulation member, 
 
 wherein a curved proximal face of the articulation member slidably engages a curved distal face of the base during operation, and 
 wherein actuation of the first and second drive members in opposite axial directions within the shaft causes the articulation member to rotate about the articulation axis and thereby articulate the wrist in the plane. 
 
     
     
       17. A surgical tool, comprising:
 a drive housing; 
 a shaft that extends from the drive housing along a longitudinal axis; 
 a wrist arranged at an end of the shaft and including:
 a base providing a pivot shaft that extends along an articulation axis; and 
 an articulation member defining an aperture that receives the pivot shaft, the articulation member being rotatable about the articulation axis; and 
 
 a linkage assembly actuatable to articulate the wrist in a plane and including:
 a first drive member extending within the shaft from the drive housing and being operatively connected to the wrist at a first drive pin of the articulation member; and 
 a second drive member extending within the shaft from the drive housing and being operatively connected to the wrist at a second drive pin of the articulation member, 
 
 wherein the first and second drive pins are longitudinally aligned with and defined on angularly opposite sides of the aperture, and 
 wherein actuation of the first and second drive members in opposite axial directions within the shaft causes the articulation member to rotate about the articulation axis and thereby articulate the wrist in the plane.